• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.3
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• pp.236-241
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• 2008

The effect of organic solvent mixture ratio on the rheology property of slurry and thickness control of ceramic green sheet was investigated. For selecting a suitable dispersant multiple light scattering method was used to evaluate the particle migration velocity and variation of clarification layer thickness. Using the selected dispersant the dispersion property of solution according to solvent mixture ratio was investigated. Binder and plasticizers were added to formulate slurries and their viscosity was evaluated according to solvent mixture ratio. Ceramic green sheets with average thickness of 30, 50 urn were fabricated via tape casting and their thickness tolerances measured. As a result according to solvent mixture ratio the solution and slurry properties varied and for the mixture ratio of ethanol/toluene of 80/20 the ceramic green sheet with the lowest thickness tolerance was obtained.

• Journal of the Korean Wood Science and Technology
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• v.24 no.3
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• pp.65-71
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• 1996

In the design of wood structures, the consideration of the dynamic load effect has been increased. Generally, damping ratio is presented as the method of considering dynamic load effect. So, the relationship between joint type and damping ratio was investigated. It has been known that the joint extremely damp the dynamic load in wood structures. Static test was performed to determine the effects of nail size and friction area on joint strength and stiffness. Joint strength and stiffness were increased with nail size. However, the static properties of joint was not affected by friction area. Cyclic test was performed to determine the effects of nail size, friction area and load magnitude on damping ratio, Damping ratio was affected by all factors. Increasing the width of the bottom plate was suggested as the most adequate method to increase the damping ratio without the reduction of the static properties of the structures.

• Steel and Composite Structures
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• v.22 no.3
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• pp.677-690
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• 2016

In this paper, the effect of damping ratio on nonlinear dynamic analysis response and dynamic increase factor (DIF) in nonlinear static analysis of structures against column removal are investigated and a modified empirical DIF is presented. To this end, series of low and mid-rise moment frame structures with different span lengths and number of storeys are designed and the effect of damping ratio in DIF is investigated, performing several nonlinear static and dynamic analyses. For each damping ratio, a nonlinear dynamic analysis and a step by step nonlinear static analysis are carried out and the modified empirical DIF formulas are derived. The results of the analysis reveal that DIF is decreased with increasing damping ratio. Finally, an empirical formula is recommended that relates to damping ratio. Therefore, the new modified DIF can be used with nonlinear static analysis instead of nonlinear dynamic analysis to assess the progressive collapse potential of moment frame buildings with different damping ratios.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.4
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• pp.1640-1647
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• 2012

The allocation to third parties in increase of capital is increasing in KOSDAQ firms. With this trend, they cause many problems which involves stock price manipulation. Under this condition, this study analyzes stock price reaction by event study to 197 cases of 81 KOSDAQ companies that allocated to third parties in increase of capital between the year of 2007 and 2009. And we find determinants of cumulative abnormal return by using multiple regression. Results of this research are as follows. First, in case of excess return of (-5, +5), it reveals positive excess return significantly at 1% significance level during 4 days before payment day(event day). But it reveals negative excess return significantly at 1% significance level during 5 days after payment day. Second, in case of excess return of (-40, +40), it reveals positive excess return significantly at 1% significance level during 40 days before payment day(event day). But it reveals negative excess return significantly at 1% significance level during 40 days after payment day. Third, in case of excess return of (0, 1 year), it reveals negative excess return significantly at 1% significance level during 1 year after payment day. Fourth, significant determinant of cumulative abnormal return to (-5, +5) was firm size with positive effect. Significant determinants of cumulative abnormal return to (-40, +40) were reserve ratio and debt ratio. Reserve ratio has positive effect But debt ratio has negative effect. Significant determinants of cumulative abnormal return to (0, 1 year) were firm size, debt ratio, reserve ratio. equity ratio to large shareholder. Firm size, debt ratio, equity ratio to large shareholder have negative effect. But reserve ratio has positive effect.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.2
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• pp.48-57
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• 2003

The objective of this study is to review and verify whether the functions and effect of roadside trees generally hewn in theory are actually realized in urban roads and how well they are performed if the function and effect are realized. The study was conducted with a focus on 3 functions and effects including roadside tree's urban landscape improvement function (green area visibility ratio), effect of introducing green area within a city, and urban green network building function. The major study results are as follows: First, the average green area visibility ratio of 41 study areas is currently about 25.90%. The green area visibility ratio of commercial area within downtown was lowest among 5 road types. It showed that it is possible to raise the average green area visibility ratio up to 32.49% through roadside tree management and additional plantation. Second, in a section between Paldal Mountain and Suwon City Hall where there is no forest fragments and parks at all, a green area of 4,826 roadside trees represented 2.4% of total area and served as the only linear green area. Third, an analysis of 15 cities in Kyonggi province showed that urban forests are concentrated in outskirts. The suey showed that because forest fragments and parks exist in a form of points in urban areas, roadside trees are the only green areas that link each other and build a network.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.101-106
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• 2020

The research was conducted with the aim of knowing the effect of the CAMELS ratio either partially or simultaneously on stock prices. The CAMELS ratio (Capital, Asset Quality, Management, Earning, Liquidity) is used to measure the soundness of a bank, where by the better the soundness of the bank, the more profitable the bank will be for potential investors and other interested parties. The population of this research consists of the four state banks documented on the Indonesia Stock Exchange over the 2012-2019 period. The sample selection technique is a saturated sampling. This study provides the results that partially CAR has a significant effect on the share price of government banks listed on the IDX. Meanwhile, NPL, NPM, ROA, and LDR do not have a significant effect on stock prices of state banks listed on the IDX. The results of the regression analysis show that, together the CAMELS ratio, which is proxied by CAR, NPLS, NPM, ROA, and LDR has a positive and significant influence on the share price of state-owned banks documented on the Indonesia Stock Exchange, so this can be used as a reference for investors in predicting the share price of a state-owned bank before investing in shares.

• Journal of Ocean Engineering and Technology
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• v.2 no.2
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• pp.122-129
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• 1988

Recently with the rapid development in marine and shipbuliding industries such as marine structures, ship and chemical plants, there occurs much interest in the study of corrosion fatigue characteristics which was closed up an important role in mechanical design. In this study, the 5086 Al-alloy was tested by use of rotary bending fatigue tester. The retardation effect of overload on the corrosion fatigue crack propagation in sea environment was quantitatively studied. 1) Retardation effect of corrosion fatigue crack propagation is most eminent when overload ratio is 1.52, overload magnitude corresponds to about 77% and 55% of yield strength and tensile strength respectively. 2) After overload ratio 1.52 was used, retardation of corrosion fatigue crack growth rate is largely retarded and quasi-threshold stress intensity factor range($\Delta\textrm{K}_{th}$) appears. 3) According to m of experimental constant, retardation effect of corrosion fatigue crack propagation corresponds to about 25% of constant stress amplitude when overload ratio is 1.52. 4) When overload ratio 1.52 was used, retardation parameter (RP) decreases to about 0.43 and corrosion sensitivity (S)decreses to about 2.1.

• Journal of Environmental Health Sciences
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• v.32 no.6
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• pp.578-584
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• 2006

This research was conducted to estimate the effect of C/N ratio control on composting of TNT (2,4,6 trinitrotoluene)-contaminated soil. Glucose or acetone was selected to control C/N ratio of the contaminated soil. The C/N ratios of the controlled experiment and no controlled one were 26.0 and 6.6, respectively. During 45days, the degradation efficiency (96.0 or 91.8%) of acetone or glucose C/N ratio controlled soil was higher than that (78.4%) of no C/N ratio controlled case. The first order degradation rate constant of glucose or acetone C/N ratio control was 0.0641 or 0.0820/day. This constant was over twice 0.0356/day of no C/N ratio control. The C/N ratio control with glucose or acetone also showed a rather high $CO_2$ evolution than that without C/N ratio control. It was proven that C/N ratio control for composting of TNT-contaminated soil improved the treatment efficiency.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.6
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• pp.173-181
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• 2000

The stability of a structural plate is a crucial problem which causes wrinkling and buckling. In this paper, the effect of the pattern of spot-welding points in the two rectangular plate on the shear buckling load is studied with respect to the thickness, the aspect ratio of plates, the number of welding spots. Buckling coefficient of the simple plate was compared with that of two plates with various conditions to extract the effect of buckling strength. The effect of the number of welding spots are studied in two directions, longitudinal and transverse directions. The concluded that the reinforcement effect was maximized when the aspect ratio was close to 1.5 and that the effect of number of welding spots in longitudinal direction was larger than that in transverse direction.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.6
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• pp.1023-1030
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• 2001

The tensile properties of short nylon6 fiber reinforced NR and SBR have been investigated as functions of diameter ratio(DR), interphase condition, fiber aspect ratio(AR), and fiber content. The short-fiber(DR=3 and AR=2) reinforced SBR did not show the dilution effect for all interphase conditions. And the short-fiber(DR=3 and AR=2) reinforced NR did not show the dilution effect except for the no-coating. The better interphase condition, the lower dilution effect at same DR. The tensile moduli are significantly improved due to fiber content and diameter ratio at same interphase condition. The pull-out force increased with the DR. The better interphase condition, the higher pull-out force at same DR. It is found that the DR and AR have an important effect on tensile properties.